Regulator



May 12, 1936. K. H. HUBBARD REGULATOR Filed J l 6, 1931 2 Sheets-Sheet 2 INVENTOR B Karl HHubbam? Y A) w ATTORNEY Patented May 12, 1936 PATENT OFFICE REGULATOR Karl H. Hubbard, Rochester, N. Y., assignor to Taylor Instrument Companies, Rochester, N. Y., a corporation of New York Application July 6, 1931, Serial No. 548,962

17 Claims.

This invention relates to fluid-pressure actuated regulators.

Fluid-pressure actuated regulators in the past have, had several undesirable characteristics, one of which was that a large temperature or physical change was required-in order to open or close the valve or other device to be regulated and another of which was that the force available at the motor end of the regulator was not as large as is usually desired. These two objectionable characteristics were not independent of each other, but instead were related in such a way that while it was possible to design a regulator that avoided, either one of the two-mentioned objections, the other objectionable characteristic has then been present to an exaggerated degree.

The present invention has for its purpose a fluid-pressure actuated .regulator of high sensitivity, in which asmall temperature or other physical change is efiective to actuate a device to be regulated with a force that is ample to satisfy ordinary requirements.

For a clearer understanding of the invention, reference is made to the drawings wherein Fig. 1 represents a regulator system in which the primary portion thereof is in part vapor pressure actuated; and Fig. 2 represents a modified form of the invention in which the primary portion of the system-is essentially fluid operated, as dis- 80 tinguished from the vapor pressure arrangement shown in Fig. 1. Referring to Fig. 1, the numeral I represents a control mechanism such as a valve or the like for regulating the flow of steam or other fluid through the conduit tube 2. As herein disclosed the device is represented as a temperature regulator and steam is used as the heating medium.

The bulb 3 represents the usual form of temperature-sensitive element exposed to the conditions to be controlled, which bulb is connected by the capillary 4 to a primary pressure-sensitive capsular diaphragm 5. The bulb 3, the capillary l and diaphragm 5, which are herein referred to as the primary system, are in part filled with a 4 suitable liquid and the remainder of the space thereof contains vapor of this liquid, so that the primary system is essentially vapor pressure actuated.

The diaphragm 5, which is mounted upon a 5 fixed support 6, has its movable face bearing against a movable platform I. This platform forms part of a balancing scales, including balance beam 8, the weight pan 9 suspended therefrom, pivot Ill and the platform supporting frame 55 II. This platform under the influence of the weight 90 opposes the expansive movement'of the diaphragm 5 and its opposing resistance may be varied by changing the amount of the weight.

A second capsular diaphragm I2 is fastened at one of its ends to the lower side of the platform 5 I, while its other end is attached to the fixed support l3, so that the movable or active end of the diaphragm I2 bears against the platform 'I. The arrangement is such that the expansive movement of, the diaphragm 5 moves the platform 10 I to compress the diaphragm l2, whereby variations in pressure in the diaphragm 5 are transmitted to the diaphragm l2.

The diaphragm H which is filled with a liquid to be described, is connected by a small conduit 15 28,- to a condensing chamber l5 consisting of an enlargement 15a of the conduit surrounded by a metallic body provided with radiating fins 65b. The condensing chamber i5 is also connected with a vaporizing chamber it, consisting of an an enlargement l6a of the conduit surrounded by the heated space Nib defined by the metal wall 60 and suitably lagged by heat-insulating material. The enlargement I6a in the vaporizing chamber is in turn connected by the conduit 22 to the in- 25- terior of the regulator diaphragm as. This diaphragm at its upper end is attached to a fixed support and its lower end is fastened to the valve stem 23 to move the same against the action of the coil spring 24 surrounding this stem. so

The regulator diaphragm is surrounded by a heating medium preferably a steam coil I! having an intake Ila. The coil H is connected by means of a conduit it with the space Nib of the vaporizing chamber, and by means of a conduit 35 l9 and a valve |9a the exhaust of the steam from 1 the space llib may be controlled as desired; The coil ll, conduit [8 and the fluid connection between the enlargement l6 and the diaphragm M are heat insulated, as indicated by the hood 20 40 and the conduit cover 2| so as to maintain in conjunction with the insulated walls I60, a vaporizing heat about the enlargement Ilia, the fluid connection 22 and the diaphragm l4. From the foregoing it should be understood that the 4B diaphragm [2, the portion 28 of the conduit and the condensing chamber l5 up to the vaporizing chamber l6 contain liquid, while the portion of the system including the vaporizing chamber It, the conduit 22 and the diaphragm ll contain vapor of this liquid.

In order to protect the relay diaphragms 5 and i2, adjustable stops 25 and 21 are provided on the stationary parts ta. and. 61) for cooperation with a bar 26' on frame l It will be appreciated that there may be a for the diaphragm l2, the diaphragm i4 and the conduit connecting the same, this choice of filling medium being determined by the operating temperature of the diaphragm I4 and its pressure rating. For a temperature of 212 F. at the diaphragm I 4 and an effective area thereof of three square inches, ethyl ether is suitable as a filling medium. The vapor pressure of ethyl ether at 212 F. is about lbs. gauge and at 150 F. about 26 lbs. gauge. Assuming the temperature at the condensation chamber to be about,

150 F. and at the .diaphragm I about 212 F., the operating pressure range lies between 26 lbs. and 85 lbs., or at least may be safely assumed to lie between 30 lbs. and 70 lbs. and for this range the total force made available at the diaphragm M for an eifective area of three square inches is about lbs.

The effective cross-sectional area of the diaphragm 5 is considerably larger than that of the diaphragm i2 and the ratio of their areas may be assumed to be of the order of ten to one. The filling medium to be used in the primary system, including the bulb 3 and diaphragm 5 depends upon the desired temperature range of the instrument and upon the pressure rating of the diaphragm 5. In the arrangement described, ethyl chloride is'considered as a suitable filling medium for the primary system with ethyl chloride vapor filling the upper portion of bulb 3.

The operation of the system of'Fig. 1 is as follows:

The vapor and fluid in bulb 3 expand or contract according to the temperature to be regulated. The point of regulation, 1. e. the point of temperature to be maintained is determined by the weight 9a. The greater this weight, the higher the temperature maintained and vice versa. The diaphragm I2 is not acted upon until the force of the ditphragm 5 exceeds the opposing force of the weight 9a exerted through the balance upon the platform 1. Further increase of pressure in diaphragm 5 then effects downward movement of the platform 1 to compress diaphragm i2 and the fluid contained therein.

The force exerted by the vapor pressure in the primary system upon the effective area of dia phragm 5 is counteracted and balanced by the sum of forces acting in opposition. Aside from the force exerted by the weight through the lever system of the balance, the principal opposing force is the force exerted by the pressure in the secondary system upon the effective area of the diaphragm i2. The force derived from the action of the weight 9a remaining constant, balance is maintained generally by variation of pressure in the secondary system in proportion to the variations of pressure in the primary system. The pressure in the secondary system is increased incident to transfer of liquid from the condensator side to the vaporizer side of the system and vaporization thereof, and the pressure is decreased incident to transfer of vapor from the vaporizer side to the condensator side of the system and condensation thereof.

The principal advantage of the apparatus described is. the high degree of sensitivity, obtained by 'the ratio of the efiective area of the diaphragm 5 and the diaphragm H, in the above example assumed as ten to one. This advantage, however, can be practically realized only by application of the condensator vaporizer unit, which described above.

makes it possible to keep the bulb 3 within prac-.-

. tical limits. Without the arrangement for converting the liquid transferred to the diaphragm it into vapor form, the bulb 3 would have-to be so large as to be impracticable. Due to the fact that the volume of a given mass of vapor is much greater than the volumeof the same mass of liquid, vaporizing the liquid displaced from diaphragm I2 and transferred to the diaphragm i4 avoids the use of an excessively large bulb 3.

The modification shown in Fig. 2 shows the fluid-pressure actuated regulator with the primary portion of the system completely filled with liquid, 1. e., the bulb 3 of the temperature-sensitive element, as well as the capillary 4 and the diaphragm 5 are completely filled with liquid, as distinguished from the liquid and vapor pressure filled primary system of Fig. 1.

This change to the completelyfilled liquid.

pressure system from the combined liquid and vapor pressure primary'system, necessitates the use of a diaphragm 5 that is small and capable of standing a higher pressure than the corresponding diaphragm shown in Fig. 1 and also requires that the diaphragm l2 of the second modification have an effective area considerably larger than that of the diaphragm 5.

In this modificationthe mounting of the diaphragm 5 also differs from the mounting of the corresponding diaphragm in the arrangement of Fig. 1, since in this instance the diaphragm 5 at one of its ends is mounted on the arm 3i which, in turn, is pivoted on the pin 32 secured on extension 30 of the support. The free end of the diaphragm 5 engages the upper surface of the platform 7, the lower surface of which platform engages the free end of the diaphragm H, as in the foregoing modification. The upward movement of the lever 3| and consequently the diaphragm attached thereto is limited by an adjustable stop in the form of a set screw 33 mounted on an arm 34 which, in turn, is fastened to an extension 35 of the support. The set screw 33, against which lever 3i always engages, determines the point of control, i. e. the temperature or pressure at which action occurs. The remainder of the second system in which corresponding parts are designated by the same reference characters may be identical in structure and function with the corresponding portion of the system of Fig. 1, previously described.

The primary system including the bulb 3, capillary 4 and diaphragm 5 may be completely filled with liquids such as ethyl chloride or mercury, while the portion of the secondary system, including diaphragm i 2, the conduit 28 and the condensing chamber l5 may be filled with ethyl ether. The remainder of the secondary system, including the vaporizer IS, the conduit 22 and the diaphragm I! are filled with vapor of ethyl ether, as The operation of the second form of the invention will be readily understood from the previously described. operation of the regulator of Fig. 1 without further explanation.

In order to explain the energy relations of the arrangement of this invention, let it be assumed that the temperature of the primary sensitive bulb 3 is increased a small increment. The energy supplied by the filling medium, regardless of whether the system is solid filled or vapor pressure actuated, is equal to the change in volume at the first relay diaphragm 5, multiplied by the pressure. When the first relay diaphragm expands, this increment'of energy furnished by the filling medium, is used in three different ways. If the two relay diaphragms and I2 act as springs, part of the energy is used to change the shape of these two diaphragms. A certain amount of liquid flows from the second relay diaphragm into the vaporizing chamber l6, and the amount of this energy isegual to the volume of the liquid, multiplied by' the pressure in the regulator diaphi lgm II. This is the energy that the primary sensitive bulb 3 actually supplies for the operation of the regulator I4. I! the primary tube system is vapor pressure actuated, part of the energy increment of the filling medium is used to raise the counter-balancing weight.

When a small increment of temperature is applied to the sensitive bulb 3 there is, of course, a corresponding expansion of the regulator diaphragm i4. 'Ihe energy involved in this expansion is equal to the increment in the volume of the diaphragm, multiplied by the gauge pressure of the vapor filling of this diaphragm. As before stated, the energy supplied to the regulator diaphragm by the primary sensitive bulb is equal to the volume of liquid forced into the vaporizing chamber l6, multiplied by the pressure in the regulator diaphragm M. It is evident that when this liquid'is vaporized, its volume is greatly increased and therefore the change in the volume of the regulator diaphragm is much greater than the volume of liquid forced into the vaporizing chamber. It follows that the energy supplied to the regulator bellows by the primary sensitive bulb is only a small fraction of the energy supplied by the entire mechanism.

In order to distinguish between diaphragms 5, i2 and H in the claims, the diaphragm 5 may be termed primary relay diaphragm; the diaphragm l2 a secondary relay diaphragm and the diaphragm H a regulator diaphragm. The term force as used in the claims is intended to be inclusive of displacement.

I claim:

1. The method of operating a regulator, which comprises developing a response corresponding to a change in a condition to be regulated, utilizing said response to move a definite corresponding quantity of liquid to a position where it is to be vaporized, vaporizing said quantity of liquid, and transmitting the resulting vapor to said regulator to actuate the same.

2. l.he method of operating a regulator, which comprises developing a force proportional to a change in a condition to be regulated, utilizing.

said force to move a proportional quantity of liquid to a position where it is to be vaporized, vaporizing said quantity of liquid, and transmitting said vapor to said regulator to actuate the same.

3. The method oi operating a temperature regulator, which comprises developing a force proportional to an increase in a temperature to be regulated, utilizing said force to move a proportionalquantity of liquid to a position where it is to be vaporized, vaporizing said quantity of liquid, transmitting said vapor to said regulator to actuate the same, condensing a part of said vapor on a reduction in said temperature and restoring the resulting liquid to its original position.

4. The method of actuating a vapor-operated regulator, which comprises developing a small amount of primary energy in response toa change in a condition to be regulated, utilizing said primary energy to apply to said regulator from an external source by vaporizing independently oi the regulator a definite quantity of liquid, an amount of energy much greater than the amount of said primary energy but proportional thereto.

5. In a regulating device, means for developing a force corresponding to a change in a condition to be regulated, a vapor-actuated motor for operating a regulating device, a closed system partially filled with liquid terminating in said motor, and means apart from the regulating medium for vaporizing a definite quantity'oi' said liquid corre-' sponding to said force.

6. In apparatus of the character described,

means including a primary relay diaphragm responsive to conditions to be controlled, control mechanism, a secondary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating the control mechanism, a fluid and vapor connection between the secondary relay diaphragm and the regulator diaphragm, said connection being uninterrupted by valve mechanism, vaporizing means in said connection, and a source of heat for heating saidvaporizing means.

'7. In apparatus of the character described, means including a primary relay diaphragm responsive to conditions to be controlled, control mechanism, a secondary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating the control mechanism,

a fiuid and vapor connection between the secondary relay diaphragm and the regulator diaphragm, said connection being uninterrupted by valve mechanism, vaporizing means in said connection, and a source of heat surrounding said vaporizing means and said regulator diaphragm.

8. In apparatus of the character described, means including a primary relay diaphragm responsive to conditions to be controlled, control mechanism, a secondary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating the control mechanism, and a normallyfopen conduit including a vaporizer, said conduit terminating in said secondary diaphragm and said regulator diaphragm, said cone duit being partially filled with liquid.

9. In apparatus of the character described, a

primary relay diaphragm, a temperature-sensitive device including vapor for actuating said primary relay diaphragm, a secondary relay dia-- dary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating control mechanism, a fluid connection between the secondary 'relay diaphragm and the regulator diaphragm, a vaporizer in said connec-.

tion, and means for heating said vaporizer, the effective area of the primary diaphragm being smaller than the efi'ective area of the secondary relay diaphragm.

11. In apparatus of the character described, means including a primary relay diaphragm. responsive to conditions to be controlled, control mechanism, a secondary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating the control mechanism, a fluid connection between the secondary diadary diaphragm.

12. In apparatus of the character described, means including a primary relay diaphragm responsive to conditions to be controlled, control mechanism, a secondary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating the control mechanism, a

fluid connection between the secondary diaphragm and the regulator diaphragm, including a vaporizing chamber and a condensing chamber, said vaporizing chamber serving to vaporize liquid moving past a given point in said connection toward the regulator diaphragm and said condensing chamber serving to condense vapor moving past said given point toward the secondary diaphragm, the effective area of the primary diaphragm being materially larger than the effective area of the secondary diaphragm.

13. In apparatus of the character described, means including a primary relay diaphragm responsive to conditions to be controlled, control mechanism, a secondary relay diaphragm acted upon by the primary diaphragm, a regulator diaphragm for operating the control mechanism, a fluid connection between the secondary diaphragm and the regulator diaphragm, including a vaporizing chamber apart from said regulating diaphragm, means for maintaining a vaporizing heat about the vaporizing chamber and the regulator diaphragm, said fluid connection being uninterrupted by valve mechanism, and means between the vaporizing chamber and the secondary diaphragm for condensing vapors moving from the vaporizing chamber toward the secondary diaphragm.

14. In apparatus of the character described, a balancing beam pivotally supported intermediate its ends, a weight pan supported on one end of said beam, a platform supported on the other oend of said beam, means including a primary relay diaphragm responsive to conditions to be controlled, said primary diaphragm having its movable portion engaging one side of said platform, a secondary relay diaphragm having a movable portion engaging the other side of said platform, and control mechanism governed by said secondary relay diaphragm.

15. In apparatus of the character described, a balancing beam pivotally supported intermediate its ends, a weight pan supported on one end of said beam, a platform supported on the other end of said beam, means including a primary relay diaphragm responsive to conditions to be controlled, said primary diaphragm having its movable portion engaging one side of said platform, a secondary relay diaphragm having a movable portion engaging the other side of said platform, the effective areas of .said primary and said secondary diaphragms being unequal, and control mechanism governed by said secondary relay diaphragm.

16. In apparatus of the character described, a balancing beam pivotally supported intermediate its ends, a weight pan supported on one end of said beam, a platform supported on the other end of said beam, means including a primary relay diaphragm responsive to conditions to be controlled, said primary diaphragm having its movable portion engaging one side of said platform, a secondary relay diaphragm having a movable portion engaging the other side of said platform, the effective area of said primary diaphragm being greater than the efiective area of said secondary diaphragm, and control mechanism governed by said secondary relay diaphragm.

17. In a temperature regulating device, a valve for controlling a heating medium, a motor for operating said valve, a thermostat for injecting a vaporizable liquid into said motor upon changes of temperature, a heating chamber surrounding said motor, an auxiliary source of heat, and heating means for said chamber operative from said auxiliary source of heat.

KARL H. HUBBARD. 

